This invention relates to hybrid engine systems including a combination of heat engine such as an internal combustion engine and a fuel cell where the fuel cell bottoms the heat engine. Although hybrid engine systems have been discussed in the past, the prior art has always combined an internal combustion or turbine as a bottom to a fuel cell. The present invention reverses the order and obtains many benefits by using a fuel cell as a bottom to a heat engine such as a direct fired reciprocating engine.